The present invention is directed generally to call routing, and more particularly, to a system that efficiently transfers telephone calls and provides separate billing records for each leg of the call.
Many times in the business world, it becomes necessary to transfer a telephone call from one terminating party to another. This is quite common in call center applications that customers typically reach by dialing toll free numbers, such as telephone numbers beginning with 800 or 888. In these cases, an agent at one location may transfer a call to an agent at another location who can better assist the customer. During the transfer, agents may briefly confer in order to exchange information about the customer before one of the agents drops out. In other cases, an agent for one business transfers the customer to an agent for another business after the first transaction completes. For instance, an airline reservation agent may offer to transfer the customer to an agent of a car rental agency after the customer completes a ticket reservation.
While conventional techniques offer quick call transfers, they have several disadvantages. One disadvantage is that conventional techniques typically transfer calls from the terminating location. The new call is effectively hairpinned (or tromboned) through the first terminating switch to the second terminating switch. The first terminating switch remains in the call until the call completes. This leads to an inefficient use of telephone company facilities.
Another disadvantage from the inefficient transfer of the calls is difficulty in billing for telephone companies. In the case of an airline call that is transferred to a car rental agency, the telephone company providing the toll free service would like to charge the first portion of the 800/888 call to the airline and the second portion to the car rental agency. However, the telephone company has no direct knowledge of the transfer and, therefore, cannot easily produce separate billing records.
FIG. 1 is a block diagram of a conventional communications network that performs call transfers. Tandem switch 1100 interconnects a customer telephone 1200 with an agent terminal, such as agent terminal 1300 or 1400, via the Public Switched Telephone Network (PSTN).
Customer telephone 1200 connects to a local Private Branch Exchange (PBX) or Class 5 telephone switch, such as local switch 1210, over a standard telephone line. Local switch 1210 connects to a Service Control Point (SCP) 1220 using a standard data connection. SCP 1220 contains directory numbers (DNs) for routing telephone calls through the network. Local switch 1210 also connects to tandem switch 1100 over the PSTN using facilities, such as a standard ISUP trunk.
The agent terminals might include a combination of a telephone and a personal computer, such as agent terminal 1300, or simply a telephony-capable personal computer, such as agent terminal 1400. Agent terminals 1300 and 1400 connect to tandem switch 1100 via the PSTN and respective local PBX or Class 5 telephone switches, such as local switches 1310 and 1410.
Agent terminals 1300 and 1400 also connect to respective local Computer Telephony Integrated (CTI) servers 1320 and 1420 via standard data connections, such as Ethernet or X.25 data connections. Local CTI servers 1320 and 1420 are computers that contain a data connection, such as an Ethernet or X.25 data connection, to local switches 1310 and 1410, respectively.
Tandem switch 1100 is a tandem level telephone switch connected to SCP 1120 and billing system 1140. SCP 1120 contains DNs for routing telephone calls through the network. Billing system 1140 is a database that maintains billing records for telephone calls routed through tandem switch 1100.
When a customer dials a toll free number on customer telephone 1200 to obtain service by an agent using agent terminal 1300, for example, customer telephone 1200 transmits the telephone call to local switch 1210. Local switch 1210 queries SCP 1220, using a technology such as Signaling System 7 (SS7), to perform local toll free processing. Based upon data, such as the dialed digits, the calling number, etc., SCP 1220 directs local switch 1210 to route the call through the PSTN to tandem switch 1100.
Upon receiving the call, tandem switch 1100 performs long distance SCP processing by querying SCP 1120, using a technology such as SS7. Based upon data, such as the dialed digits, the calling number, the time-of-day, etc., SCP 1220 directs tandem switch 1100 to route the call through the PSTN to local switch 1310.
In response, tandem switch 1100 connects customer telephone 1200 to agent terminal 1300 via local switch 1310. Local switch 1310 also transmits call data, such as the calling number and the dialed digits, to local CTI server 1320. Based on this data, CTI server 1320 populates the screen on agent terminal 1300 with information about the customer. The agent then converses with the customer and processes the call transaction.
If, during the course of call handling, the agent decides to transfer the call to a second agent, such as the agent using agent terminal 1400, the agent uses agent terminal 1300 to send a transfer command to local switch 1310 either directly or indirectly via CTI server 1320.
One way that local switch 1310 can complete the transfer is to route the call back into the PSTN. The call may very well route up to tandem switch 1100 and then back through the PSTN to agent terminal 1400 via local switch 1410. Once the connection is established, the agents may briefly converse before agent terminal 1300 drops out. Alternatively, the first agent may not confer with the second agent at all and drop out before the second agent answers. However, no matter when agent terminal 1300 drops out of the call, all of the voice communication facilities remain in effect until the customer ends the call. In other words, local switch 1310 and the voice facilities to and from this switch remain part of the connection for the duration of the call.
In an alternative technique, the connection is completed through the PSTN without involving tandem switch 1100. However, even if tandem switch 1100 is involved in the connection to agent terminal 1400, the connection appears as a new call to tandem switch 1100. Tandem switch 1100 does not recognize that the connection is merely a second leg to the original call.
In yet an another technique, private facilities are used to connect agent terminals 1300 and 1400, instead of the PSTN. Private facilities are more likely to be used if both agents work for the same company instead of partner companies. However, in all these alternatives, all the voice communication facilities to and from local switch 1310 remain in use until the customer ends the call.
When the customer eventually places customer telephone 1200 on-hook and ends the call, tandem switch 1100 produces a billing record and sends it to billing system 1140. The conversation time recorded in this billing record includes both the time that the customer spoke with the first agent, as well as the time that the customer spoke with the second agent. Tandem switch 1100 provides no information in the billing record that allows the telephone company to allocate the conversation time to each leg of the call.
As a result, a need exists to overcome the disadvantages of the conventional techniques and to provide cost efficient call transfers and accurate billing records.